1. Field of the Invention
The present invention relates to a power tools, and particularly to a roof shovel. More specifically, the invention relates to a power shovel for removing shingles and attached nails from a roof to facilitate re-roofing, which shovel may be pneumatically or electrically actuated.
2. Description of Related Art
Commonly, when a house or other building has to be re-roofed, it is necessary to first remove the existing roof materials. Removing these materials, namely the shingles and nails attaching them to the existing roof structure, is a difficult process which has traditionally been accomplished by forcing a shovel or a similar tool under the shingles to pry them loose along with the attached nails.
This requires a great deal of physical exertion and often results in many of the nails either being forcefully ejected from the roof structure so that they pose a danger as they fly through the air, or, remaining embedded in the roof structure so that they must be removed from the roof structure separately of the shingles. In either case the task of cleaning up the removed roofing materials is made more difficult because the nails have been separated from the shingles while being removed.
One way to reduce the effort involved and the tendency of the nails to be separated from the shingles during the removal of the roofing materials is to utilize vibrating or reciprocating and otherwise movable shovel type elements driven by a variety of power sources to pry the shingles and attached nails from the roof structure. A number of tools having shovel type elements of the above described type have been disclosed in the prior art.
U.S. Pat. No. 4,095,752, issued Jun. 20, 1978 to Jean-Claude Pomeret and Henry Bonnevaux, discloses a motorized shovel apparatus having a cart mounted swiveling support arm, a pneumatic motor driven winch assembly, and a shovel with a pneumatic vibrator disposed between the handle and the shovel blade. The shovel, which is suspended from the winch assembly on the support arm, has controls in its handle adapted to operate the pneumatic motor driven winch assembly and the pneumatic vibrator so that the shovel may be easily operated with a minimum of physical effort. The apparatus of Pomeret and Bonnevaux is intended to be used to dig holes in the ground in cases where the use of a large mechanical shovel is not economical or is not possible due to lack of space.
U.S. Pat. No. 5,009,131, issued Apr. 23, 1991 to Brian J. Alto and Gregory F. Alto, discloses a long handled tool adapted for stripping roof shingles which utilizes a reciprocating blade slidably mounted over a shingle lifting plate to pry shingles from a roof structure and cut the shingle nails. When a trigger on the end of the handle of the tool is squeezed, an electric motor and gearing assembly connected to an offset crank causes the blade to reciprocate along an axis perpendicular to the leading edge of the lifting plate. The tool is effective at removing shingles and nail heads, but leaves the body of the nail embedded in the roof structure.
German Patent Number 925,428, issued Mar. 21, 1955, discloses another device which utilizes a motor and gearing assembly connected to an offset crank to reciprocate a blade member in front of the device. The device is a hand held power scraper for cleaning plane surfaces.
U.S. Pat. No. 4,858,503, issued Aug. 22, 1989 to John H. Dike, Jr., discloses a long handled shingle removing tool having a pivoting shovel element on the bottom end of the handle which is actuated by a trigger on the top end of the handle. The shovel element is pivoted upwardly by a-pneumatic drive attached thereto to pry the shingles from the roof structure after the shovel element has been forced under a group of shingles.
U.S. Pat. No. 5,076,119, issued Dec. 31, 1991 to Steven C. Wenz, discloses a roof shingle removing apparatus having a wheeled shovel like prying member with a blade attached to its forward edge. The blade on the apparatus of Wenz reciprocates along an axis parallel to the leading edge of the shovel-like member which is adapted to cut the nail heads to allow the shingles to be easily removed. The device has wheels and a deflector and cuts a wide path.
U.S. Pat. No. 5,098,165, issued Mar. 24, 1992 to James L. Jacobs and Larry D. Rogers, discloses a wheeled cart connected to a roof mounted guide system that allows the roof to be traversed at various positions along different travel paths. The cart has a reciprocating blade attached to its forward edge that follows the contour of the roof structure to dislodge shingles and nails therefrom. The apparatus of Jacobs and Rogers relies on an electric motor to reciprocate the blade and a complicated blade support assembly to insure that the blade follows the contours of the roof structure.
German Patent Number 2,300,668, issued Jan. 8, 1974, discloses another device for removing materials from a surface. The device includes a reciprocating plate which pries beneath the surface of the material being removed. The above mentioned device is specifically adapted for removing carpeting from a floor and has a spiked wheel and guide assembly which draws the carpet upward after it has been pried from the floor.
U.S. Pat. No. 4,302,894, issued Dec. 1, 1981 to Sam F. Emma, discloses a wheeled device having a long handle extending upward from its base and a movable shovel like member extending forward therefrom. The shovel member on the device of Emma is adapted to pivot downward to dump the material held in the shovel member. The device is manually operated and can be operated standing up without bending or stooping for shoveling snow and the like.
U.S. Pat. No. 3,625,295, issued Dec. 7, 1971 to Samuel D. Gunning, discloses an air hammer. U.S. Pat. No. 5,505,340, issued Mar. 19, 1985 to Yantzen et al. discloses a device adapted for breaking up concrete, asphalt, rock and the like in congested areas which uses a pneumatic chamber for biasing the handle in a neutral position and hydraulic power for reciprocating action.
However, none of the prior art discloses a shovel having a pneumatically driven reciprocating shovel blade or an electrically powered reciprocating shovel blade which is specifically adapted to remove roofing shingles and attached nails without separating them from each other.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.